Answer:30
Step-by-step explanation: act like both of the triangles are there, that is a rectangle 6 times 10 equals 60. 60 divided by 2 is 30
You can obtain the a number for which they all divisors by calculating the least common multiple.
This way:
85 = 5*17*1
17=17*1
19=19*1
4=2^2 *1
2=2*1
The least common multiple is: 5*17*19*2^2 = 6,460.
Then 84, 17, 19, 4 and 2 are all divisors of 6,460.
Because like terms you add or subtract together to make it easier to do the problem. just like you do with whole numbers. you add an subtract to make the answer simpler.